Fading channel emulation for a large number of mobile devices is a common challenge in testing and characterizing mobile network resources, such as eNodeBs (eNBs) in long term evolution (LTE) or LTE-Advanced networks. It has been demonstrated that comprehensive testing of a mobile network early in a development cycle, under challenging realistic load and radio channel conditions, can prevent shortfalls in key performance indicators or costly outages of the fully deployed network.
In mobile networks, heterogeneous networks, and relay networks, packet-oriented user data transmission has become a default method, even for traditionally circuit-switched modes of communication, such as voice. This is because packet-oriented user data transmission can more readily exploit space, time, and frequency-diverse channel conditions to maximize traffic, subject to fairness and quality-of-service (QoS) criteria. A central responsibility of a mobile network resource (e.g., an eNB) is the dynamic allocation and/or scheduling of transmission resources, such as time, frequency, modulation and coding, power, or the like, and of multi-antenna mode of operation (e.g., spatial multiplex, diversity, beam forming, or the like). Relevant industry standards for mobile networks, such as the Third Generation Partnership Project (3GPP), do not define details of such scheduling algorithms, and, as a result, providers of mobile networks often utilize proprietary scheduling algorithms.
The characteristics and performance of a scheduling algorithm may be studied using analytical and/or simulation methods. However, such methods generally require the introduction of simplifying assumptions, some of which may not, or only approximately, be satisfied in practice. Furthermore, the implementation of a complex communication algorithm may deviate from an ideal model due to unavoidable trade-offs and unintentional defects or idiosyncrasies associated with the particular implementation. Such issues have to be dealt with on a continuous basis since new standards are released and additional communication services, transmission modes, or the like are introduced.